One of the leading challenges facing designers of hearing aids involves achieving acceptable battery life without impacting the weight, size, and form factor of the hearing aid. Rechargeable batteries with acceptable size and weight for use in a hearing aid can supply adequate power for approximately one day, thus requiring daily recharge. However, daily recharging is not always available, such as when the user is on a camping trip or vacationing. Thus, there is often a tradeoff between a large heavy rechargeable battery or a smaller lighter non-rechargeable battery that has to be replaced frequently.
Most hearing aids today, use inexpensive disposable batteries, such as the common zinc-air batteries. These batteries have a smaller weight and form factor than rechargeable batteries with acceptable battery life, allowing the hearing aid size and weight to be reduced and increasing desirability for potential customers. However, disposable non-rechargeable batteries require regular replacement, increasing the operating cost of the hearing aid in terms of the cost of replacement batteries, which can be significant over the useful life of the hearing aid. Further, such disposable batteries contribute to landfills and may include corrosive and poisonous chemicals that can leak into the environment.
In the following description, the use of the same reference numerals in different drawings indicates similar or identical items.